New Mexico (NM) GS-24 Structural Steel Erection EXAM
with Questions and Answers/Plus a Rationale Updated 2026
A+/Instant Download PDF
MAIN DOMAINS
1. OSHA Safety Regulations and Fall Protection
2. Structural Steel Erection Procedures and Rigging
3. Welding, Bolting, and Connection Details
4. Site Planning, Foundation Verification, and Crane Operations
1. When is a controlled deck zone (CDZ) permitted to be established during a structural steel
erection project under OSHA standards?
A. During the installation of all metal decking on multi-story commercial structures
B. Only on structures up to 30 feet in height when traditional fall protection is completely
infeasible
C. Only on structures up to 30 feet in height for metal decking operations where traditional
fall protection creates a greater hazard
D. During any roofing or decking phase where workers are trained as competent persons
CORRECT ANSWER : C
Rationale: OSHA 1926.760 permits controlled deck zones only on structures up to 30 feet in
height during initial metal decking operations where conventional fall protection is proven to be
infeasible or creates a greater hazard. Option A is incorrect because height and feasibility limits
apply. Option B is incorrect because feasibility, not mere height alone, dictates the allowance.
Option D is incorrect because training alone does not justify a CDZ.
2. What is the minimum compressive strength percentage required for concrete in footings and
piers before structural steel erection can safely commence?
A. 50% of specified compressive strength
B. 70% of specified compressive strength
C. 85% of specified compressive strength
D. 100% fully cured strength
CORRECT ANSWER : B
, Rationale: OSHA and industry standards require concrete in footings and piers to reach at least
70% of its specified compressive strength before absorbing loads from structural steel erection.
Option A is insufficient to support heavy steel loads safely. Options C and D exceed standard
baseline safety requirements for starting erection work.
3. Which of the following rigging components must be removed immediately from service if it
exhibits wear exceeding 10% of the original diameter of any individual wire?
A. Synthetic web slings
B. Alloy steel chain slings
C. Wire rope slings
D. Shackles and turnbuckles
CORRECT ANSWER : C
Rationale: Wire rope slings must be removed from service if there is corrosion, distortion, or
wear exceeding 10% of the original diameter of any individual outer wire. Option A refers to
synthetic materials evaluated by cuts and burns. Option B uses stretched links and gouges.
Option D relies on dimensional distortion rather than individual outer wire wear.
4. In structural steel bolting, what is the primary purpose of using direct tension indicator (DTI)
washers?
A. To lubricate the bolt threads during high-torque tightening
B. To provide a direct visual and measurable indication that the correct bolt tension has
been achieved
C. To prevent galvanic corrosion between dissimilar metals in coastal environments
D. To act as a secondary locking mechanism against dynamic vibrational loads
CORRECT ANSWER : B
Rationale: DTIs feature small protuberances that flatten progressively as tension increases,
giving a measurable gap indicating proper bolt preload. Option A is incorrect as lubricants are
applied separately. Option C addresses corrosion using coatings or isolation. Option D
describes lock washers rather than DTIs.
5. According to OSHA Subpart R, what is the maximum allowable height for multi-story column
erection without requiring a re-plumb check?
A. One story
, B. Two stories
C. Three stories
D. Four stories
CORRECT ANSWER : B
Rationale: Multi-story columns are typically erected in two-story lifts before requiring a formal
re-plumb and alignment check. Option A is too conservative for standard steel sequences.
Options C and D exceed the structural stability threshold for un-plumbed multi-story tiers.
6. What action must be taken immediately if anchor bolts are found to be out of tolerance or
damaged prior to column placement?
A. Modify the base plate holes in the field using an oxygen-acetylene torch without engineering
approval
B. Notify the project structural engineer of record and obtain written approval for any
modification or repair
C. Force the column base plate into position using heavy rigging and hydraulic jacks
D. Cut off the damaged anchor bolts and weld new ones directly to the foundation surface
CORRECT ANSWER : B
Rationale: Field modifications to structural anchor bolts or base plates require formal
engineering review and written authorization to maintain structural integrity. Option A is
prohibited due to metallurgical damage from unapproved torch cutting. Option C risks yielding
the bolts. Option D fails to meet structural load transfer standards.
7. When hoisting structural members, what type of signaling system must be used if the crane
operator's view is obstructed?
A. Two-way radio communication only
B. Automated laser sensor tracking systems
C. Standard hand signals or dedicated radio communication by a qualified signal person
D. Visual flashing light arrays installed on the boom tip
CORRECT ANSWER : C
, Rationale: OSHA requires a qualified signal person using standardized hand signals or
dedicated radio communication when the operator's direct line of sight is obstructed. Option A
restricts communication exclusively to radio when hand signals are also valid. Options B and D
are supplemental or non-standard methods.
8. What is the mandatory minimum overlap for metal decking sheets installed in a structural steel
floor system?
A. 1 inch at side laps
B. 1.5 inches at side laps and 2 inches at end laps
C. 3 inches at all laps regardless of manufacturer specifications
D. No overlap is required if welds are spaced tightly
CORRECT ANSWER : B
Rationale: Industry standards and manufacturer specifications generally require at least 1.5
inches of side lap overlap and 2 inches of end lap overlap for metal decking. Option A is too
small for proper load distribution. Option C is excessively arbitrary. Option D ignores basic
diaphragm action requirements.
9. Which welding process is most commonly utilized for field shear connector stud welding onto
steel beams?
A. Shielded Metal Arc Welding (SMAW)
B. Gas Tungsten Arc Welding (GTAW)
C. Automatic Electric Arc Stud Welding
D. Flux-Cored Arc Welding (FCAW)
CORRECT ANSWER : C
Rationale: Shear studs are almost exclusively installed using specialized automatic electric arc
stud welding equipment with ceramic ferrules. Option A is used for structural joints, not rapid
stud attachment. Option B is slow and used for precision pipe. Option D is used for
manual/semi-automatic structural joints.
10. What defines a "competent person" in the context of structural steel erection safety regulations?
A. Any worker who has completed an OSHA 10-hour construction course
B. An individual who has a professional engineering license in New Mexico
with Questions and Answers/Plus a Rationale Updated 2026
A+/Instant Download PDF
MAIN DOMAINS
1. OSHA Safety Regulations and Fall Protection
2. Structural Steel Erection Procedures and Rigging
3. Welding, Bolting, and Connection Details
4. Site Planning, Foundation Verification, and Crane Operations
1. When is a controlled deck zone (CDZ) permitted to be established during a structural steel
erection project under OSHA standards?
A. During the installation of all metal decking on multi-story commercial structures
B. Only on structures up to 30 feet in height when traditional fall protection is completely
infeasible
C. Only on structures up to 30 feet in height for metal decking operations where traditional
fall protection creates a greater hazard
D. During any roofing or decking phase where workers are trained as competent persons
CORRECT ANSWER : C
Rationale: OSHA 1926.760 permits controlled deck zones only on structures up to 30 feet in
height during initial metal decking operations where conventional fall protection is proven to be
infeasible or creates a greater hazard. Option A is incorrect because height and feasibility limits
apply. Option B is incorrect because feasibility, not mere height alone, dictates the allowance.
Option D is incorrect because training alone does not justify a CDZ.
2. What is the minimum compressive strength percentage required for concrete in footings and
piers before structural steel erection can safely commence?
A. 50% of specified compressive strength
B. 70% of specified compressive strength
C. 85% of specified compressive strength
D. 100% fully cured strength
CORRECT ANSWER : B
, Rationale: OSHA and industry standards require concrete in footings and piers to reach at least
70% of its specified compressive strength before absorbing loads from structural steel erection.
Option A is insufficient to support heavy steel loads safely. Options C and D exceed standard
baseline safety requirements for starting erection work.
3. Which of the following rigging components must be removed immediately from service if it
exhibits wear exceeding 10% of the original diameter of any individual wire?
A. Synthetic web slings
B. Alloy steel chain slings
C. Wire rope slings
D. Shackles and turnbuckles
CORRECT ANSWER : C
Rationale: Wire rope slings must be removed from service if there is corrosion, distortion, or
wear exceeding 10% of the original diameter of any individual outer wire. Option A refers to
synthetic materials evaluated by cuts and burns. Option B uses stretched links and gouges.
Option D relies on dimensional distortion rather than individual outer wire wear.
4. In structural steel bolting, what is the primary purpose of using direct tension indicator (DTI)
washers?
A. To lubricate the bolt threads during high-torque tightening
B. To provide a direct visual and measurable indication that the correct bolt tension has
been achieved
C. To prevent galvanic corrosion between dissimilar metals in coastal environments
D. To act as a secondary locking mechanism against dynamic vibrational loads
CORRECT ANSWER : B
Rationale: DTIs feature small protuberances that flatten progressively as tension increases,
giving a measurable gap indicating proper bolt preload. Option A is incorrect as lubricants are
applied separately. Option C addresses corrosion using coatings or isolation. Option D
describes lock washers rather than DTIs.
5. According to OSHA Subpart R, what is the maximum allowable height for multi-story column
erection without requiring a re-plumb check?
A. One story
, B. Two stories
C. Three stories
D. Four stories
CORRECT ANSWER : B
Rationale: Multi-story columns are typically erected in two-story lifts before requiring a formal
re-plumb and alignment check. Option A is too conservative for standard steel sequences.
Options C and D exceed the structural stability threshold for un-plumbed multi-story tiers.
6. What action must be taken immediately if anchor bolts are found to be out of tolerance or
damaged prior to column placement?
A. Modify the base plate holes in the field using an oxygen-acetylene torch without engineering
approval
B. Notify the project structural engineer of record and obtain written approval for any
modification or repair
C. Force the column base plate into position using heavy rigging and hydraulic jacks
D. Cut off the damaged anchor bolts and weld new ones directly to the foundation surface
CORRECT ANSWER : B
Rationale: Field modifications to structural anchor bolts or base plates require formal
engineering review and written authorization to maintain structural integrity. Option A is
prohibited due to metallurgical damage from unapproved torch cutting. Option C risks yielding
the bolts. Option D fails to meet structural load transfer standards.
7. When hoisting structural members, what type of signaling system must be used if the crane
operator's view is obstructed?
A. Two-way radio communication only
B. Automated laser sensor tracking systems
C. Standard hand signals or dedicated radio communication by a qualified signal person
D. Visual flashing light arrays installed on the boom tip
CORRECT ANSWER : C
, Rationale: OSHA requires a qualified signal person using standardized hand signals or
dedicated radio communication when the operator's direct line of sight is obstructed. Option A
restricts communication exclusively to radio when hand signals are also valid. Options B and D
are supplemental or non-standard methods.
8. What is the mandatory minimum overlap for metal decking sheets installed in a structural steel
floor system?
A. 1 inch at side laps
B. 1.5 inches at side laps and 2 inches at end laps
C. 3 inches at all laps regardless of manufacturer specifications
D. No overlap is required if welds are spaced tightly
CORRECT ANSWER : B
Rationale: Industry standards and manufacturer specifications generally require at least 1.5
inches of side lap overlap and 2 inches of end lap overlap for metal decking. Option A is too
small for proper load distribution. Option C is excessively arbitrary. Option D ignores basic
diaphragm action requirements.
9. Which welding process is most commonly utilized for field shear connector stud welding onto
steel beams?
A. Shielded Metal Arc Welding (SMAW)
B. Gas Tungsten Arc Welding (GTAW)
C. Automatic Electric Arc Stud Welding
D. Flux-Cored Arc Welding (FCAW)
CORRECT ANSWER : C
Rationale: Shear studs are almost exclusively installed using specialized automatic electric arc
stud welding equipment with ceramic ferrules. Option A is used for structural joints, not rapid
stud attachment. Option B is slow and used for precision pipe. Option D is used for
manual/semi-automatic structural joints.
10. What defines a "competent person" in the context of structural steel erection safety regulations?
A. Any worker who has completed an OSHA 10-hour construction course
B. An individual who has a professional engineering license in New Mexico